The present invention relates to a vehicle seat and particularly, to a vehicle seat used as a rear seat in a vehicle and being capable of forming a spacious space in a vehicle cabin with a seat back flattened to a seat cushion side.
Some of the rearmost seat backs of vehicle seats provided in two rows or three rows are capable of flattening to a seat cushion side. As a result, it is possible to form a spacious space at a rear portion in a vehicle, and hence, a larger baggage can easily be loaded.
As a configuration that enables the seat back to be flatted to the seat cushion side, Japanese Unexamined Patent Application Publication No. H3-65445 (Patent Literature 1) describes a structure in which a front link and a rear link are interposed between a seat cushion frame and a base frame of a vehicle floor.
Further, Japanese Unexamined Patent Application Publication No. 2015-20602 (Patent Literature 2) describes a dive-down seat taking a configuration in which, when a seat back is further flattened with a support leg at a front end portion of a seat cushion landed on a floor, the relation between links is broken whereby the seat cushion is urged to be moved forward to make a lower end of a front leg come off from an insertion opening of a lock mechanism. With this configuration, the dive-down seat can flatten the seat back completely because restrictions can be released on the forward movement of the seat cushion as well as on the forward flattening of the seat back, so that a back surface of the seat back can be utilized as a carrying surface of a cargo room.
Further, Japanese Unexamined Patent Application Publication No. 2015-214258 (Patent Literature 3) describes a configuration in which a cushion frame and a vehicle floor are connected through link members to make bridges therebetween.
As vehicles are enhanced in function, there has emerged a vehicle whose floor is made to be higher than that of those in prior art because components are assembled under a rear seat and the floor of a cargo room.
In the vehicle in which floors at the rear seat and the cargo room are famed to be high as above, it is preferable that, when the seat cushion is folded with the seat back flattened to the seat cushion side, the upward back surface of the seat back becomes almost the same height with the surface of the cargo room which is a little higher than the floor surface. With the configuration taken like this, a spacious space can be formed at a rear portion inside of the vehicle cabin, and hence, it becomes possible to load a larger baggage easily.
However, in the configuration described in Japanese Unexamined Patent Application Publication No. H3-65445, consideration is not taken into making the upward back surface of the seat back, in a state of being folded with the seat back flattened to the seat cushion side, reside at almost the same height with the surface of the cargo room which is a little higher than the floor surface. As a result, in the seat described in Japanese Unexamined Patent Application Publication No. H3-65445, the upward back surface of the seat back, in a state of being folded with the seat back flattened to the seat cushion side, protrudes beyond the surface of the cargo room which is a little higher than the floor surface.
Further, in the dive-down seat described in Japanese Unexamined Patent Application Publication No. 2015-20602, the configuration is taken in which, when the seat back is further flattened with the front end portion of the seat cushion landed on the floor, the relation between the links is broken whereby the seat cushion is urged to be moved forward to make the lower end of the front leg come off from the insertion opening of the lock mechanism. Due to this configuration, an effort to restore the relation once broken between the links becomes necessary in returning the seat cushion to the original position.
On the other hand, in Japanese Unexamined Patent Application Publication No. 2015-214258, the structure is described in which the upward back surface of the seat back of the rear seat, in a state of being folded with the seat back flattened to the seat cushion side, becomes almost the same height with the surface of the cargo room which is a little higher than the floor surface. As the configuration in which the seat back is folded by being flattened to the seat cushion side, the configuration is taken that connects the cushion frame to the floor surface of the vehicle through the link members.
However, in the configuration described in Japanese Unexamined Patent Application Publication No. 2015-214258, the structure is taken in which a portion on the floor surface side of the link member connecting the cushion frame to the floor of the vehicle protrudes beyond the seat cushion. In the structure like this, a restriction by the link member is exerted to the space in which the feet of the passenger seated on the seat cushion are put, and thus, there is a possibility of hurting the passenger at the rear seat in amenity.